Bomb nose fuse



' Sept. 27, 1938.

H. M. BRAYTON BOMB NOSE FUSE Filed oct. 11, i937 Tlf/3.5.

, Haro/J Shag/fo?? Patented` Sept. 27, 1938 UNITED STATES PATENT oFFicE5 Claims.

The invention relates to an improved nose fuse designed primarily foraerial drop bombs but not necessarily restricted thereto.

The improved fuse is of the general type in which a ring pin and adetonator to be fired thereby, are both held normally in safetypositions but are armed ready for operation when the bomb travels a safedistance from the craft by means of which it is launched, detonationbeing effected by impact. Fuses of this general character haveheretofore been of rather complicated and expensive nature and haveusually required a great many machine operations and special machineryfor performing same. The present invention, however, aims to provide agreatly simplified construction which may be easily and inexpensivelymanufactured without necessarily requiring special shop equipment, theconstruction, however, being such that no loss in safety, sensitivity,or efficiency, results from the simplification.

In the improved construction, I utilize a single pin to hold a detonatorcarrier in safety position when said pin occupies a normal rearwardposition, and to ilre the detonator upon impact after said pin has beenmoved, under the influence of a propeller, to a forward armed position,in which latter position, it allows movement of said detonator carrierto armed position. While this general idea has heretofore been proposed,I make unusually simple and inexpensive provision whereby the pin isdirectly driven by the propeller and is forwardly threaded to its armedposition, doing away with parts heretofore used for this purpose andconsequently reducing cost and enabling more easy and rapid manufacture.

With the foregoing and minor objects in'view,`

the invention resides in the novel subject matter hereinafter describedand claimed, description being accomplished by referenceto theaccompanying drawing.

Fig. 1 is a front elevation of a fuse constructed in accordance with theinvention.

Fig. 2 is a vertical longitudinal sectional view as indicated by line2-2 of Fig. 1, showing the normal safety positions of parts.

Fig. 3 is a fragmentary view similar to Fig. 2 but illustrating theparts in armed position.

A preferred construction is shown in the drawing and will be ratherspecically described, with the understanding, however, that Within thescope of the invention as claimed, variationsmay be made.

A forwardly tapered fuse body 5 is shown for connection in any preferredway with the nose of a bomb. 'I'his body is provided with an axialcylindrical bore 8 and with a transverse bore 1 intersecting said bore8. A carrying bolt 8 for the usual detonator 9 is slidably mounted inthe bore 1 and a spring I0 is provided to move said 5 bolt from thesafety position of Fig. 2 to the armed position of Fig. 3. 'I'his springmay well thrust against a plug or cap Il which closes one end of thebore 1, the body 5 being preferably crimped at I2 to hold said plug orcap in place. l0 When the bolt 8 is in the armed position of Fig.

3, the detonator 9 is in position to fire the explosive i3 upon firingof saiddetonator.

A plunger i4 is slidable in the bore 6 and is itself provided with anaxial bore I5, a shear pin l5 I6 being employed to hold said plungeragainst movement with respect to the fuse body 5, until said plunger isdriven rearwardly by impact, causing shearing of said pin I6. Theplunger is also held against rotation in the bore 6 by means 20 of a pinor screw I1 driven into an opening in the body 5 and engaging alongitudinal key-way or groove i8 in the periphery of said plunger. Thisplunger is provided at its front end with an enlarged striking head I9spaced forwardly 25 from the body 5, and when this head strikes theground or any stationary object, the plunger is operated to cause thering pin, hereinafter described, to ilre the detonator 9.

The firing pin 20 is threaded at 2l in the bore 30 i 5 of the plungerI4, and the rear end of this firing pin is provided with a reducedportion 22 received normally in a recess 23 in the bolt 8, to hold thisbolt in the safety position shown in Fig. 2. A safety pin 2l passesthrough alined 35 openings in the fuse body 5, the plunger i4 and thefiring pin 28 to hold all parts in the positions of Fig. 2 from the timeof manufacture until the bomb is placed in the usual rack or the likeupon the craft by which it is to be carried, said pin 40 23 being thenwithdrawn.

A propeller 25 is provided for rotating the firing pin 2li in adirection to thread it forwardly as the bomb descends, said propellerbeing suitably connected with thefront end of said firing pin 20. 45 Inthe present showing, the propeller 25 is provided with a rearwardlyprojecting axial stub 26 which is threaded into the front portion of theplunger bore i5, the rear end of said stub being separably connectedwith the front end of said 50 firing pin, the connection beingpreferably accomplished by providing said stub with a groove 21 andproviding said firing pin with a rib 28 removably received in saidgroove. The conventional arming wire (not shown) may-be passed through55 either of the eyes 29 on the'fuse body 5, and engaged with either ofthe openings 30 in the propeller 25, to hold the latter againstaccidental rotation after withdrawal of the safety pin 23, said armingwire being of course pulled from engagement with the eye and propellerwhen the bomb is dropped.

With the parts positioned as in Fig. 2, with the exception that thesafety pin 26 is withdrawn, the bomb descends. During descent, thepropeller 25 rotates the ring pin 20 in a direction to forwardly threadsaid pin in the plunger I4, thereby withdrawing the pin end 22 from therecess 23 of the bolt 8 and allowing the spring I0 to shift this bolt tothe armed position of Fig. 3. The propeller preferably continues todrive the firing pin 20 for a few revolutions after arming of the bolt 8has been effected, the forward movement of the pin being limited bymeans of a shoulder 3| thereon striking the rear end of the plunger i4.By the time this occurs, the propeller stub 26 has threaded entirely outof the plunger Ill and the connection 21, 28 allows said propeller tobecome entirely disconnected from the fuse. When the plunger head I9strikes any object on the continued descent of the bomb, the plunger ldand ring pin 20 are driven rearwardly from the armed position of Fig. 3,causing the pin end 22 to fire the detonator 9, which in turn res theexplosive I3 and that within the bomb.

From the foregoing, taken in connection with the accompanying drawing,it will be seen that novel and advantageous provision has been made forcarrying out the objects of the invention, and while preferred featureshave been shown, attention is again invited to the possibility of makingvariations within the scope of the invention as claimed.

I claim:

1. In a bomb nose fuse having detonator carrying means and means formoving said detonator carrying means to armed position; a firing pinactive when in a rearward position to hold said detonator carrying meansin safety position and active to fire the detonator when drivenrearwardly by impact from a forward armed position, said ring pin havingdirect threaded engagement with another portion of the fuse, and apropeller connected with the front end of said firing pin for rotatingthe same in a direction to cause forward threading of said firing pin tosaid armed position, in which it releases said detonator carrying means.

2. In a bomb nose fuse, a fuse body, detonator carrying means in saidbody, ring pin carrying means slidable longitudinally of said body andheld against movement except under impact, a firing pin having athreaded connection directly with said firing pin carrying means, saidfiring pin normally engaging said detonator carrying means and holdingthe same in safety position, a propeller connected with the front end ofsaid firing pin for rotating the same to cause forward movement of saidfiring pin to armed position, and means for moving said detonatorcarrying means to armed position when said ring pin releases saiddetonator carrying means.

3. In a bomb nose fuse, a fuse body, detonator carrying means in saidbody, a plunger slidable longitudinally in said body, means holding saidplunger against movement with respect to said body except under impact,a firing pin threaded in said plunger and normally engaging saiddetonator carrying means to hold the same in safety position, apropeller connected with the front end of said firing pin for rotatingthe same to cause forward movement of said firing pin to armed position,and means for moving said detonator carrying means to armed positionwhen said firing pin releases said carrying means.

4. In a bomb nose fuse, a fuse body having an axial bore which opensthrough its front end and a transverse bore which intersects said axialbore, a spring-armed detonator-carrying-bolt slidable in said transversebore, a plunger slidable in said axial bore and itself having an axialbore, means for holding said plunger against movement with respect tosaid fuse body except under impact, a firing pin threaded in said axialbore of said plunger and normally engaging said detonatorcarrying-boltto hold the same in safety position, and a propeller connected with thefront end of said firing pin for rotating it in a direction to threadsaid ring pin forwardly to armed position in which it releases saiddetonator-carrying-bolt.

5. In a bomb nose fuse, a fuse body, detonator carrying means in saidbody and means for moving said detonator carrying means to armedposition, a plunger slidable longitudinally in said fuse body andprojecting forwardly therefrom, means for holding said plunger againstmovement with respect to said fuse body except under impact, a firingpin threaded in said plunger and normally engaging said detonatorcarrying means to hold the same in safety position, and a propeller infront of said plunger and having a rearwardly projecting axial stub,said stub being threaded removably into the front end of said plungerand having a separable driving connection with the front end of saidring pin, said propeller and its stub serving to forwardly thread saidring pin to armed position in which it releases said detonator carryingmeans, said stub then unthreading completely from said plunger andseparating cornpletely from said firing pin.

HAROLD M. BRAYTON.

